:evil: I don't think the number of rounds matter as long as there's sufficient debris to give you a 1% chance or greater... .From Wiki

"For every 150,000 debris produced in a battle, there is a 1% chance that a moon will coalesce. The maximum chance of moon accretion is 20% (3,000,000 debris).

The calculation is performed on a per-battle basis; any debris in orbit at the time of a battle is not included in determining if a moon is formed.

Because the moon is the result of battle, the defending planet is the owner of any moon that is formed. Moon creation is immediate after the battle, and does not consume the debris field; therefore, collecting the debris field will not interfere with the process. :

Number of rounds doesn't matter, as long as enough debris is produced. The only difference is that if the battle only lasts one round, the losing side won't get the message saying "A new moon was formed." He/she will just get a msg that the battle ended in the first round. But the moon will be there (if it formed).

On the other hand, if the moon does not form, the losing side will not get the report saying that the moon chance was X%. (The winning side will still get the report though.)